Pawl conveyer for continuous heating furnaces



Aug. 8, 1933. R. E. TALLEY PAWL CONVEYER FOR CONTINUOUS HEATING FURNACES Filed May l5, 1931 2 Sheets-Sheet l INVENTOR )im 5, m17

R. E. TALLEY Aug. 8, 1933.

PAWL CONVEYER FOR CONTINUOUS HEATING FURNACES Filed May l5, 1951 2 Sheets-Sheet .2

INVENTOR @MAQ/ef. 76% m PatentedfAug. 8, 1933 grenier 'fofFF-llCEi ff;4

PAWL coNvEYER FoR CONTINUOUS HEAT- `INGsummons M i RandalE. Talley,'lrwin, Pa., assigner to Georgie J. Hagan Company,iPittsbu1-gh, Pa., a Corpora'- tion of Pennsylvania Application-May 15', 1931. serial No. 537,156.2

4 claims. l(ci. ees-6)" f This invention relatesA to heating furnaces, particularly to improvements invconveying mechanism `for continuous heating furnaces and itis among the objects thereof to provide conveying 5 apparatus which shall be. especially applicable for the conveying of bars, sheets, rounds, annular blanks and the like which areof such shape 'that they' cannot readily be pushed through the furnace, one against the other.

The invention briefly consists of a movable hearth member disposed longitudinally of a furnace comprising one or' more` `reciprocating members provided with self-aligning Work-engaging pawls which are normally disposed to engage the Work in one direction of movement of the reciprocating member and adapted to pass underneath the Work in the returnimovement of the reciprocating member. E i

"The invention further provides for coordination of the door operating Vand conveyer reciprocating mechanisms. f i

These and other objects will become more apparent-from a consideration of the accompanying drawings forming a part hereof, in` which like reference characters designate like parts and in which Figure 1 is a longitudinal-.vertical section of a furnace showing conveyer` mechanism embodying the principles `ofY this invention; Figure 2 a cross sectional View` ofthe conveyer 3o mechanism taken along the linesiII-f-ILbfFig. 1*; and Fig. 3 a Wiring diagram of 'the'electrical connections which diagrammatically killustrates the'motonfthe motorcontrol, andufmotor start-v ing elements for coordinating `the movements'of the conveyerand door operating mechanisms.

. With reference to Figures 1 and 2 of the drawings, the structure therein illustrated comprises an enclosing Wall structure consisting` of `Vend Walls 1 and 2,k side Walls, and a roof 4 which ,50 ancing counterweight 9, and the door 7 being similarly mountedbut adapted to be motor operated through a chain r10 andoperating crank 1l, gearsreduction unit 12, a door motor 13 and a limit switch generally designated at 14.

The conveyer mechanism 5 consists of a pair ofv reciprocating rails 15 disposed in longitudinalA 9 19 toa floor bracket 20. The link is loosely cvon- 60 nected tothe. rails 15 `by a slotted opening 21 engaging the cross bar :17 s hovvn` inligure 2. Mounted on the reciprocating rails arev a' plurality ofV pawls 23 having Weighted ends 424 which normally rest yagainst the bottom of the rails and hold them with theirufwork-engaging faces 25 perpendicular to ,thev llinerof travel of' the reciprocating rails. j i

The engaging pawls are 'mounted in `longituolinalV spaced relation, as shown` in Figureml, their spacing corresponding to the spacing of the Work which in4 the illustration consistsof flat bars 26 which bars are manually or automatically vpushed from the receiving platform r2'7 onto the guide members 16, the bars-beingf75 illustrated as extending across and .supported on theI guides v16 in Figurev 2 'of the ldrawings.` Y The reciprocating rails 'are actuated bya connecting. rod 28'Vjoinedmv to link 18 at 29` `and i Y mounted on a crank 30 which is rotated through 80 'a gear drive 3l by a conveyer motor 32.

The operation of the conveyer motor iscontrolled by a limit switch 33 inf a mannerto be lexplained in .connection-rwith Figure v 3 Y of the drawings. d

`As shown in Figure-3, a timev clock diagrammatically Villustrated vand generally designated at 34 is',V electrically connected-to a power lline. The clockis driven by a synchronous motor 35 Whichthrougha cam 36 operates theijnovable` 90 Contact `37 that engages. with a stationary contact-38 to-close the circuit of. a control relay `39, ;Ihe control relay throughcontacts' 40 `andfil controlsv the motorstarters" 42fand 43 which energize the door operating motor 13 95 and the conveyer-motor 32. Y i Y The operation of the conveyer mechanism and the. door Voperating mechanism is briefly as follows2-T1ie time clock is set to periodically close contactsS'ZY-Si at timed intervals, there- 100 Ycausing the rails 15 to be reciprocated.` As pre- Viously explained the pawls 23 Vengage the Work 105 when the rails 15 are travelling in the directionfrorn the front towards the rear of Ythe furnace andon the return movement of the rails the pawlsv slide-under' the bars 26` and when the top ofthe pawl has .olearedthe bars', 1.10

` of the contacts 41.

they are again automatically replaced Vto their normal position with their weighted portions 24 resting on the bottom of the rails. By this reciprocating motion the bars are advanced step-by-step through the furnace until they reach the discharge opening through which they are discharged into a quenching ltank or upon a suitable transporting device. f

When the conveyor motor is energized, gear 31 isrotated counter-clockwise causing the pin 44 to pass out of-engagement with the-operating linger of limit switch 33 thus allowing the switch to close. f

After a brief interval of time, contact 40 of the control relay opens, due to the opening of the contacts 37-38 of the time clock, but current is still maintained in the coil of the motor starter 42 because limit switch 33 is closed. When the gear 31 has made one complete revolution its projectingY pin'44 will again engage the lever of the limit switch 33 and'open the con-Y tacts of this switch. This interrupts the current in the coil of the motor starter 42, the

contacts of the motor starter open and the conveyor motor stops. Simultaneously with the starting of the conveyer motor by the closing of the contacts 40 the motor for opening the discharge door 7 is also started by the closing The door operating mechanism functions in the identical manner as the conveyer mechanism described above. Both motors are started at the same time by the closing of the control relay 39 and are stopped independently by the engagement of projecting pins 44 and 45 with the respective limit switches 33 and 14 when the operating cycle of each is completed. Y

It is of course possible to operate the chargingv door 6 in the same manner as the door 7 to synchronize with the movement of the conveyer mechanism, and it is also Yevident that other means may be employedV for lsynchronizing the operation of the doorwith the movement of the conveyer mechanism so that the door is closed excepting for the brief intervals during which the work is being discharged from the furnace chamber.

It is evident from the foreging description of this invention that the conveyer mechanism constructed in accordance therewith provides simple and efficient means for conveying articles such as bars, plates, sheets,.and articles of irregular form which cannot be conveyed through a furnace by ordinary pusher types of charging mechanism, but which must be individually engaged by some conveying means to prevent their buckling and pilingup on the furnace hearth.

Although one embodiment of the invention has been herein illustrated anddescribed it will be obvious to those skilled in the art that various modifications may be made in the details of vmounted on said reciprocating railsand adapted to project above the Work supporting surface of said guides, and means for subjecting the reciprocating members Ato movement in one direction whereby the pawls engage the work and advance it through the furnace and for returning saidreciprocating member to its original position whereby the pawls are depressed to pass below -the work and the work remains stationary on its supports..

2. In a continuous heating furnace having a charging opening and a discharge opening, a door for said last named opening, automatic means for opening and closing said door, a work support in said furnace, reciprocating means extending longitudinally of and beneath the upper edge of said worksupporty a plurality ofwork engaging pawls pivotally-mounted on said adapted to advance the articles to be heated stepf by-step from the charging to the discharge end of the furnace, a motor driven door operating mechanism, a common control for energizing the starter coils of said motors, a time clock for rendering said control operative at predetermined intervals, and limit switches actuated by their respective motors to kinterrupt the circuits of said motors.

4. In a continuous heating furnace a pairrof guide rails. constituting Work supports extending longitudinally of said furnace, reciprocating bars disposed in said guide rails and adapted for sliding movement therein, work engaging pawls pivotally mounted on'said barsin transverse alinement and longitudinal spaced relation, means Vfor actuating said bars in one direction whereby said pawls engage the articles supported` by said guide rails and advanceV them toward the discharge endof rthe furnace, and means for actuating said bars in the opposite direction 4whereby the pawls are released fromtheir engagement with the work and returned to their initial position. RANDAL'E. TALLEY. 

